910 



Application of DNA-based techniques for the 

 identification of whaler sharks (Carcharhinus spp.) 

 caught in protective beach meshing and 

 by recreational fisheries off the coast of 

 New South Wales 



Ricky W. K. Chan 



School of Biological, Earth and Environmental Sciences 

 The University of New South Wales, UNSW 

 Sydney, New South Wales 2052, Australia 

 Present address: Educational Testing Centre 



The University of New South Wales 



ULD 3 East Parcel Centre 



Rosebery, New South Wales 2018, Australia 

 E-mail address sharkman@etc.unsw,edu au 



Patricia I. Dixon 



Centre for Manne and Coastal Studies 

 The University of New South Wales, UNSW 

 Sydney, New South Wales 2052, Australia 



Julian G. Pepperell 



Pepperell Research and Consulting 



PO Box 1475 



Noosaville DC, Queensland 4566, Australia 



vessels may experience difficulties in 

 identification if distinguishing parts of 

 a shark are discarded prior to confir- 

 mation of species (Stevens and Wayte^). 

 Similarly, observers of protective beach 

 meshing may find species identifica- 

 tion difficult on severely decomposed 

 sharks. Without proper identification, 

 the exact number of individual species 

 inhabiting NSW waters and the num- 

 ber of each species being landed cannot 

 be determined (Chan, 2001). 



The rise of molecular biological tech- 

 niques in marine forensic science has 

 facilitated the development of accu- 

 rate taxonomic identification of shark 

 species by sampling biological tissue 

 (Martin, 1991; Lavery 1992; Heist and 

 Gold, 1999). DNA techniques require 

 only muscle tissue, allowing biopsy 

 tissue to be taken from specimens that 

 can be released, rather than having 

 to sacrifice the shark to obtain liver 

 and heart tissue for allozyme analysis 

 (Godfrey, 1997). Methods of taxonomic 

 identification include PCR-based 

 restriction fragment length poly- 



Dennis D. Reid 



New South Wales Fishenes 



PO Box 21 



Cronulla, New South Wales 2230, Australia 



The International Union for the Conser- 

 vation of Nature's (lUCN) development 

 of the Shark Specialist Group is indica- 

 tive of the increasing environmental 

 awareness of sharks' crucial ecological 

 role as apex predators and that they 

 are being threatened by human activi- 

 ties. Although the conservation status 

 of certain carcharhinid species (Car- 

 charhinus limbatus, C. obscurus, and 

 C. plumbeus) are presently considered 

 at low risk or near threatened accord- 

 ing to the lUCN's threatened species 

 categories,' species from the genus 

 Carcharhinus are known to inhabit 

 the waters of New South Wales (NSW), 

 Australia (Stevens, 1984; Last and 

 Stevens, 1994); however their conser- 

 vation status has not been determined. 

 Known as whaler or "requiem" sharks, 

 they are also commonly caught off 

 the coast of New South Wales in com- 



mercial fisheries (Stevens and Wayte^; 

 Tanner and Liggins^), recreational fish- 

 eries (Pepperell, 1992; Gartside et al., 

 1999; Steffe et al.*) and by protective 

 beach meshing (Reid and Krogh, 1992; 

 Dudley 1997). 



Because of morphological similari- 

 ties between a number of shark spe- 

 cies in the genus Carcharhinus (Last 

 and Stevens, 1994; Naylor and Marcus, 

 1994), taxonomic identification to spe- 

 cies level has been difficult or inac- 

 curate (or both)(Stevens and Wayte^). 

 Historical catches of certain species of 

 sharks in NSW commercial fisheries, 

 recreational fisheries, and protective 

 beach meshing have been recorded to 

 genus level only (Pepperell, 1992; Reid 

 and Krogh, 1992; Tanner and Liggins'^). 

 Formally trained Australian Fisheries 

 Management Authority (AFMA) ob- 

 servers aboard commercial longlining 



1 Musick, J., and S. Fowler. 2000. Car- 

 charhinus limbatus, C. obscurus and C. 

 plumbeus In lUCN 2002. 2002 lUCN 

 red list of threatened species, http: 

 //www. iucn.org/redlist/2000index. html. 

 [Accessed 1 October 2002.1 



2 Stevens,J. D..andS. E.Wayte. 1998. A 

 review of Australia's pelagic sharks 

 resources. Fisheries Research and Devel- 

 opment Corporation project 98/107, 64 

 p. CSIRO Marine Research, GPO Box 

 1538, Hobart, Tasmania 7001 Australia. 



3 Tanner, M., and G. W. Liggins. 2000. 

 New South Wales commercial fisheries 

 statistics 1993/94 to 1996/98, 82 p. New 

 South Wales Fisheries, PO Box 21, 

 Cronulla, NSW 2230 Australia. 



■* Steffe, A. S., J. J. Murphy, D. J. Chapman, 

 B. E. Tarlinton, G. N. G. Gordon, and A. 

 Grinberg. 1996. An assessment of the 

 impact of offshore recreational fishing in 

 New South Wales waters on the manage- 

 ment of commercial fisheries. Fisheries 

 Research and Development Corporation 

 Project 94/053, 139 p. New South Wales 

 Fisheries, PO Box 21, Cronulla, NSW 2230 

 Australia. 



Manuscript approved for publication 

 24 June 2003 by Scientific Editor 



Manuscript received 13 July at NMFS 

 Scientific Publications Office. 



Fish. Bull. 101:910-914 (2003). 



